Answer: A

—Aram Boghosian/Globe Photo

Unlike a double yellow line, you can pass, make a turn, and even make a U-turn. However, a single solid yellow line is also meant to discourage passing, according to MassDOT spokesman Michael Verseckes.

Also, since it is so rare, you are likely on an older road.

“The use of the single solid yellow line is becoming less and less frequent as the Manual on Uniform Traffic Control Devices (MUTCD) has been updated to employ the use of either a double solid yellow line, or if a street is narrow enough, no line at all,’’ says Verseckes.